An internal combustion engine, such as a diesel engine, a gasoline engine, or a natural gas engine, typically includes a cylinder block for defining cylinders and a cylinder head mounted on the cylinder block. The cylinders include intake and exhaust valves that are supported by valve guides provided in the cylinder head. The intake and exhaust valves are actuated to be in open and closed position by a push rod and a rocker arm arrangement. The intake and exhaust valves are lubricated between the valve guides to prevent wear of the valves. However, unexpected increase of intake manifold pressure may reduce an amount of lubricant entering the valve guides. Such reduced amount of lubricant may not be sufficient to provide adequate lubrication for the intake and exhaust valves. Over a period of operation of the engine, undesired wear of the valve guides and/or the intake and exhaust valves may occur, effecting desired operating performance of the engine and potentially leading to premature failure of components of the engine.
China Patent Number 203,559,947 hereinafter referred as '947 patent, describes a Self-oscillation valve bridge arm component with cooling capacity. The self-oscillation valve bridge arm includes a cooling capacity that relates to a valve combination mechanism of a diesel engine. Through lubricating oil channels are formed inside parts of an intake and exhaust bridge arm components, an intake and an exhaust bridge arm and an intake and an exhaust valves. An end face of a valve rod and a bridge arm ball that can be lubricated and a cooling effect on the parts can be realized, so that the working reliability of the mechanism is improved. However, the '947 patent does not provide a lubrication system that may provide sufficient lubrication to the intake and exhaust valve at any operating condition of the engine.